Automatic locking and releasing device for shift keys on typewriters



Feb. 28, 1950 R. BUCHEL 2,499,053

AUTOMATIC LOCKING AND RELEASING DEVICE FOR SHIFT KEYS ON TYPEWRITERS Filed 001',- 17, 1945 3 Sheets-Sheet l ROBE/FT BUC HE L By Maxi/d4 ATTO/FNEVS Feb. 28; 1950 R. BUCHEL 2,499,053

AUTOMATIC LOCKING AND RELEASING DEVICE 4 FOR SHIFT. KEYS 0N TYPEWRITERS Filed Oct. 17, 1945 s Sheets-Sheet 2 [NI/EN 7'01? FOBf/FT 5001 54 5y EI'W HTTOF/VEYS Feb. 28, 1950 R BUCHEL 2,499,053

AUTOMATIC LO'CKI NG AND RELEASING DEVICE FOR SHIFT KEYS 0N TYPEWRITERS 3 Sheets-Sheet 3 Filed Oct. 17, 1945 III T q- 1E Paws/Pr 50"0/151.

ATTORNEYS I Patented Feb. 28, 1950 AUTOMATIC LOCKING AND RELEASING DEVICE FOR SHIFT KEYS N TYPE- WRITERS Robert Biichel, Gamprin, Liechtenstein Application October 17, 1945, Serial No. 622,787

In Switzerland June 1, 1945 7 Claims.

The present invention relates to an automatic locking and releasing device for a typewriter shift key. In the devices of this type now used the shift key is locked in depressed position by a pawl which is released when a typewriter key is struck. Since the carriage of the typewriter, platen, and all the mechanisms connected therewith are relatively heavy and are thus carried by the shift key in above position, it then follows that in striking a key so much of the force so exerted is used up in releasing the pawl that the particular type bar operated no longer strikes the paper about the platen with sufficient force.

The object of the present invention is to reduce the power or force required for releasing the shift key by the type key to such an extent that in normal typing the power necessary for releasing the shift key is negligible.

The present invention resides in the fact that a locking member is drawn against a stop by a spring, and a return or resetting lever counteracts the former under the action of a spring and is held in cocked position by a catch releasable by a rod connected to a member universally operated by all character keys.

The aforegoing parts are so arranged, that when the shift key is depressed, the locking member bears against the stop, thereby locking said shift key which may subsequently be released up- I on striking or depressing any character key.

The parts forming the locking and releasing mechanism may be arranged difierently in different makes of typewriters.

In principle the locking member,the resetting lever and the catch holding the latter may be in fixed position on the machine, in which case the stop and the part which pushes back the reset ting lever mustbe fitted on movable parts. If the said locking and resetting levers and the catch are mounted on a movable element as for instance the shift key, then the stop and the part which pushes the resetting lever back must be fixed.

In the accompanying drawings various embodiments of the invention are illustrated and in which Figure 1 shows on a reduced scale the shift key lever connected in the usual manner to the cylinder or platen carriage; 1

Figure 2 is a fragmental sectional view showing an embodiment comprising a locking member, resetting lever and catch in idle position all mounted on the shift key;

Figure 3 is a similar View to Figure 2 with the parts locked in shifted or upper case position;

Figure 4 shows an intermediate position of the locking device;

Figure 5 shows the locking device in position before returning to the initial Figure 2 position;

Figure 6 is a fragmental detail view showing the. locking member, resetting lever and catch mounted on the up and down moving carriage;

Figures 7, 8, 9 and 10 are similar views to Figure 6 but showing the locking member, resetting lever and locking catch mounted on the stationary frame of the machine, while the stop and resetting lever actuating member are mounted on the shift lever;

Figure 11 shows a similar arrangement to Figure9 with the exception that the resetting lever actuating member and stop are fixed on the carriage frame; and g Figure 12 is a fragmental sectional view showing one manner of connecting the locking tooth to the escapement mechanism.

Referring now to the drawings in detail, the shift key lever I shown in Figure 1 is swingably mounted in the usual manner on pivot 2 and connected at the rear thereof by means of a connection 3 to a frame 4 which carries the typewriter carriage in which is mounted the cylinder or platen 5. The frame, carriage and cylinder may be lifted or raised to upper case position by depressing the end B of the shift key I. The said key I is guided at the front thereof in the slotted plate I usually provided at the front of the typewriter. Pivotally mounted at I3 on the shift key I is a locking member 8 provided with alever arm 9. The said arm 9 is connected by means of a spring It) to a catch or locking tooth II pivotally carried by the shift key. The locking member when in normal idle position engages a roller I2 mounted on the machine frame. Also pivotally mounted on pivot I3 is a control or resetting lever l4 having an arm 23 to which is connected one end of a coiled spring I5, the opposite end of said spring being anchored on a pin I6 carried by the machine frame. The said lever I4 is provided with a second arm 24 which for co-operative engagement with the tooth I I, carries two lips I1 and I8, the lip I8 being arranged above and behind the lip I! as viewed from the right side of Figures 2 to 5.

The space or distance between the lower lip I1 and upper lip I8 is somewhat larger than the tapered end I9 of the locking tooth II so that it may slide freely between said lips. When the shift-key lover I is depressed as shown in Figure 3 in order to lift the cylinder, locking member 8 1's drawn under the roller I2 by the action ment shift mechanisms the segment is arranged movably and in other models immovably. The type bar in its movement toward the cylinder I It pushes against the beam l I la. of the shift bridge III which, by the member 503 and the guide H2 is displaceably supported in the-segment [ill for movement towards the escapement mechanism 195. As is known, there have been provided in the escapement mechanism I05 the escapement dogs I55 and i ill by which the escapement wheel I04 is alternately stopped and released, which causes the latter to turn step by step. In typewriters with segment shift arrangements the shift bridge [H with the member I03 moves downward or upward, and-in machineswithout segment shift. arrangements, the shift bridge II! is. moved horizontally only. As a rule, the type bar. lllfiacts on the beam I i ia only after traveling %.of its movement. The shift bridge HI. is provided with a cross-piece 99. in which the pulling member or rod Ellis supportedwhich is provided with a stop a. The pulling member or rod 21] is of such a design that it is. moved by the shift bridge and releases the shift pawl or catch II as soon as the type bar I00. reaches a point 5-15 mm. in front of the cylinder I in.

The stop 20a. is arranged in such away that it is away from the cross-piece 99 by a distance of 2% when the shift key is in itsposition of rest, so that, when striking a. key, the stopZfia of the pulling member 26 is not moved by the crosspiece. 59. But as soon as the shift key is moved downwards, it pulls the pawl I i so far down that the stop 29a lies against the cross-piece 99.

Now if a type bar is struck, thhe pulling member 29., is moved also, and the pawl lljumps into thev position according to Figure 4:, from which, when the type bar. returns, it moves into position of Figure 5. and, in the position of rest of the.

shift lever, after putting thespring I5. under tension, again takes the position according to Fig.- ure 1.

In a similar manner, if necessary, the pullingmembers 20 of Figures 6 to 11 can'also be, actually mounted on a pivot pin 2'! carried by the carriage frame 28. which may be moved up and down. The carriage frame 28 is engaged by a roller 29 and lifted thereby when the shift-key lever 3| is depressed or swung about its pivot 30, the roller 29 being rotatably mounted on the shift-key lever extension 32 at the rear of the pivot 30. The locking member is pressed against a roller 34by means of a spring 33, so that the carriage frame when raised will remain in lifted position due to the engagement of the bottom of the locking member with the roller 3d. catch 35 is pulled down by-thetension rod 20 and releases the resetting lever 26- which is then free to be swung about the pivot 21. against a stop 3] on the locking member 25, by the action of.a spring 35. The action of the resetting lever pressesthelocking member into cocked idle position against. the spring 33-permitting thecarriage 28 to again drop to lower position. In this downwardmovement, arm 38- of the resetting When a character ke is struck, locking lever 26 strikes against a pin 39 fixed to the frame of the machine and presses lever 26 into engagement with catch 35 and tensions spring 36 to hold the resetting lever ready for actuation by the operation of the next key.

The embodiment shown in Figure '7 comprises a locking member 4! anda resetting lever 42 pivotally mounted. on a stud or pin 43 fixed on the machine frame 45 by means of a bracket 44 secured to said frame by a bolt 45. A spring 47 also secured to the frame 45 by the bolt 48 presses against a stop or ledge 43 on the locking member 4!. An, arm 49 of resetting lever 42 is movably connected to shift-key lever 51 by means of. a slotted arm or link 55. A bolt or stud 53 on arm 49 fits slidingly in a slot 54 in arm 59 and is normally held against the bottom of said slot by a spring 52 secured at one end to the arm 49 and at its opposite end to the shift-key lever 5|. Due to the above arrangement, the spring 52. becomes tensioned when the shift-ke lever is depressed, the link 50sliding down due to the slot. and. stud arrangement. The resetting lever 42 is normally held by a catch 55 pivotally mounted on a stud Eflfixed on the machine frame, the said catch being pressed upwardly by a spring 57. The locking. roller 58 which abuts against the bottom of the locking member 4|: when the shift-key lever is depressed, is pivotally mounted on thesaid shift-key lever 5 I Figure 8 shows the locked position of the shiftkey lever 5!. As in the other forms of the inven tion, the catch. 55 .is brought out of engagement with the resetting lever by a pull on the tension rodlfl, permitting lever 42 tobe swung against thestop 43 on the member 4! and swing same intoa position to permit the roller Edto come in advance-of the said locking member upon the return. of the shift-key. lever to upper position, which actionagain swings the resetting lever by the linkfifi into engagement with the catch 55.

The embodiment shown in Figure 9 is similar to that shown in Figures '7' and 8 with thev exception that a roller this fixed to the shift-key lever 65 and replaces the link 58, saidroller normally abutting the underside of an arm 61 on a resetting lever. 63.

The Figure 10 embodiment is similar to that,

shown in Figure 9, with the exception, however, that a. roller 5.4 is. arranged on a lever 12 connected with a. shift-key lever 70 by means of a link, ll, said. arrangement replacing the roller 58 shown in Figures 7, 8 and 9 which is directly mounted. onthe shift-key lever 5!; Likewise instead of the bracket 4 3: of the Figures 7, 8, and 9 embodiments, the Figure 10 embodiment provides, a support won the machine'frame, which at its upper end has a pin or. stud lziuponwhich arepivotally mountedthe locking member 73 and resetting lever I4. A. catch 77' for engaging the resetting; lever 74 is also piyotally supported on the support 16'. A spring 'l'S-is anchored at one end on the support l6 and at its opposite end on an arm 'ifl of the reset lever 'M'and holds same againsta roller 88 on the shift-key lever l5. Upon the depression of shift-key lever 10 roller 64 is brought belowthelocking member 13 and permits the spring 81; to pull said locking member into locking engagement. with the said roller'64; During the depression of the shift-key lever, roller moves away from the arm '19 of the resetting lever '34 andipermits said resetting lever to contact pin 82 and reset the locking member 13. whentcatchl'l is released by tension rod 20.

Figure; llshows a, counterpart tothe embodiment illustrated in Figure 6. Locking member 83 is pressed against roller 81 by spring 84 fixed to bolt 85 on the frame. Roller 81 is fixed on frame part 88 which is lifted by roller 89 fixed on rear arm 90. of shift-key lever 9|. Besides locking member 83, resetting lever 93 which is pressed against roller 95 by means of spring 94 fitted on frame 88, also pivots on bolt 92 fixed on the frame of the machine. Catch 96 is pressed against resetting lever 93 by spring 91 thus locking the former in cocked position. 0n lifting frame 88 by roller 89, looking member 83 comes under roller 81 thus preventing frame 88 from dropping. When catch 96 is released by tension rod 20, lever end 98 bears against stop 86 of locking member 83, so that the lock effected by roller 81 is released, thus enabling frame 88 to drop. When the frame moves downward, roller 95 rests against resetting lever 93 and brings it again into the position locked by catch 96.

, What is claimed is:

1. In a typewriter having a frame structure, character keys, and a structure including a platen carriage and a shift-key mounted for movement from lower to upper case position with respect to said frame structure; a device for automatically locking said shift-key in upper case position and then releasing same, said device comprising a stop mounted on one of said structures, a pivotally mounted locking "member mounted on the other of said structures and normally spring pressed against said stop, a spring actuated resetting lever pivotally and coaxially mounted with the locking member, a spring urged locking catch mounted on said other structure for operative engagement with the resetting lever, the said locking member being adapted to be brought into locking engagement with the stop when the shift-key is depressed to maintain said key in depressed position, a member universally actuated for movement by each typewriter character key when said keys are operated for typewriting, and means connecting said universally actuated member with the locking catch to move the catch and bring same out of locking engagement with the resetting lever at the completion of said typewriting operation to permiit the resetting lever to swing the locking member out of locking engagement with the stop and permit the shiftkey to return to normal position.

2. In a typewriter having a frame, a platen carriage, character keys and a shift-key connected to said carriage for moving same from lower to upper case position, a device for automatically locking said shift-key in upper case position and then releasing same, said device comprising a stop mounted on the typewriter frame, a locking member pivotally mounted on the shift-key, a resetting lever pivotally mounted on the shift-key coaxially with the locking member, a locking catch pivotally mounted on the shift-key in engagement with the resetting lever, a spring connected to the locking member and locking catch to normally hold said locking member against said stop, a spring exerting a tension against the resetting lever for maintaining same in locking engagement with the catch, the said locking member being adapted to be brought into locking engagement with the stop when the shift-key is depressed to maintain said key in depressed position, a member universally actuated for movement by each typewriter character key when said keys are operated for typewriting, and means connecting said universally actuated member with the locking catch to move the catch and bring same out of locking engagement with the resetting lever at the completion of said typewriting operation to permit the resetting lever to swing the locking member out of locking engagement with the stop and permit the shiftkey to return to normal position.

3. In a typewriter having a frame, a platen carriage, character keys and a shift-key connected to said carriage for moving same from lower to upper case position; a'device for automatically locking said shift-key in upper case position and then releasing same, said device comprising a stop mounted on the type writer frame, a locking member pivotally mounted on the shift-key, a resetting lever pivotally mounted on the shift-key coaxially with the locking member, the said locking member being formed with a recess along its upper surface, a lip at the rear extremity of said recess, an upper and a lower lip on the resetting lever, the lower lip being in advance of the upper lipand extending into the locking recess, a locking catch pivotally mounted on the shift-key normally in engagement with the lower lip of the resetting lever, a spring connected to the locking member and locking catch to normally hold said locking member against said stop, a spring exerting a tension against the resetting lever for maintaining same in locking engagement with the catch, the said locking member being adapted to be brought into locking engagement with the stop when the shift-key is depressed to maintain said key in depressed position, a member universally actuated for movement by each typewriter character key when said keys are operated for typewriting, and means connecting said universally actuated member with the locking catch to move the catch and bring same out of locking engagement with the resetting lever lower lip and bring said catch into locking engagement with the upper lip during the downward stroke of any of said character keys, the said resetting lever being swung about its pivot by its spring during said movement of the catch to bring its lower lip into engagement with the locking member lip, the said connecting means disconnecting the catch from the upper lip upon the return stroke of the character key and bringing said catch between the upper lip and lower lip of the resetting lever to permiit the lower lip of said resetting lever to swing the locking member out of locking engagement with the stop and permit the shift-key to return to normal position.

4. A device according to claim 1, wherein the locking member, resetting lever and catch are mounted on the typewriter frame, and the stop is mounted on the shift-key.

5. A device according to claim 1, wherein the locking member, resetting lever, and catch are pivotally supported on the platen carriage and the stop is supported on the typewriter frame.

6. In a typewriter having a frame, a platen carriage, character keys and a shift-key connected to said carriage for moving same from lower to upper case position; a device for automatically locking said shift-key in upper case position and then releasing same, said device comprising a stop mounted on the shift-key, a

ascents setting lever arms slidable in said slot and normally resting at the bottom thereof, a-spring secured at one end to said arm and at its opposite end to the shift-key, a spring for normally pressing the locking member againstthestop, a catch pivotally mountedon the typewriter frameat one end and in looking engagement with the other of said resetting lever arms, a spring for normally maintaining the catch in said locking engagement, the said locking member being urged by its spring over the stop when the shift-key is depressed to maintain the key in depressed position and the link sliding on the pin on the resetting lever arm .to'bring the topof the slot into engagement with the pin, a member universally actuated for movement by each typewriter character key when said keys are operated for typewriting, and :means connecting said universally actuated member with the locking catch to move the catch and bring same out of locking engegment with the. resetting lever arm at the end of said typewriting operation to permit the catch engaging arm of the resetting lever to contact the locking member ledge to swing the locking member out of locking engagement with thestop and permit the shift-key to return to normal position.

7. In a typewriter having a frame, a platen carriage, character keys and a shift-key connected to said carriage for moving same from lower to upper case position; a device for automatically locking said shift-key in upper case position then releasing same, said device comprising a stop mounted on the typewriter frame, a locking member pivotally mounted on the typewriter carriage, a resetting lever'pivo'tally and coaxi'ally mounted with said locking" member, the resetting lever comprising a pair of arms, a :pin on the typewriter frame against which one of said arms normally bears, a spring connected to said arm for normally holding same against said pin, a catch pivotally mounted on the carriage, a spring for holding said catch in locking engagement with said other resetting lever a roller on the shift-key lever in engagement 'with the carriage for raising same when the shift-key is depressed, a spring for normally pressing the locking member against the stop and moving same thereabove for locking engagement therewith when the said shift- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,0155419 Smith Jan. 30, 1912 1,163,564 Schneeloch Dec. '7, 1915 

